Oh
One video led to another until finally my TikTok feed was filled with teenagers trying to grow up. They called it “heightmaxxing,” a subset of the much-dissected world of “lookmaxxing,” in which young men exchange strategies for improving their appearance in hopes of avoiding a fate of despair and loneliness. For these young men, the logic is ruthlessly effective: everything in life is better if you are tall.
The videos arrived with the narrative progression of a course program. First come explanations about “height,” or discrimination based on a person’s size. Dating was a frequent point of frustration, with tallness seen as a prerequisite for consideration.
Then, slowly but surely, strategies on what you can do about it.
Eventually, I was watching some teenagers discussing something called erda. They posted updates on their growth and compared notes on side effects. Some showed measuring tapes against marks on a wall; others labeled the videos based on the number of days they had taken them. It turns out that Erda was short for erdafitinib, an anti-cancer drug that the boys in my diet said could make them grow taller, highlighting reports of unexpected growth in children being treated for cancer. They were willing to endure debilitating symptoms to find out.
About half an hour into my conversation with Zak, a 17-year-old TikToker in New York, he told me he was preparing for the possibility of a hospital stay. He had been taking Erda on and off since he was 15, and after bouts of joint pain and nosebleeds, he expected something would eventually go wrong. “I was literally saving money every day. I was putting money aside for my job and everything else just to pay an erda medical bill.” He said he purchased the drug from overseas online sellers, initially paying $300 for a month’s supply.
Zak says size became especially important to him as he spent more time on social media. He remembers videos of women discussing how tall a man had to be to consider dating them. At school, he says he was made fun of because he was shorter than the girls in his class. “I don’t like others dominating me and I don’t like having to admire people,” he says. “I don’t know how to say this, but I feel like I’m not in control.”
Erdafitinib, sold under the brand name Balversa, was first approved in 2019 to treat certain advanced bladder cancers in adults. Doctors have also used it off-label in clinical trials on children with rare central nervous system cancers. The drug’s known side effects are nothing short of horrendous: Its prescribing information lists diarrhea, limb pain, nausea, and nails coming off their beds, as well as excess phosphate in the blood, which can cause mineral deposits in soft tissues.
In a statement, a spokesperson for Johnson & Johnson, which markets Balversa, said it was concerned about online content that appears to show young people using prescription drugs for unauthorized purposes or without medical supervision. “It has not been approved to increase height, and its safety and effectiveness have not been established for this purpose or for use in children or adolescents,” they said, adding that the company urges patients to consult qualified healthcare professionals about treatment and to only use medications from verified sources and under medical supervision.
Zak reports nosebleeds, very dry skin and pain that made ordinary movements difficult. “As I stretched my arm, it felt like my wrist was going to rip off,” he says. “When I woke up, my spine felt like it was bent. I had to spend an hour stretching to get my spine to feel better.” Even then, he said, the pain persisted.
When we talk, he has stopped taking the medication, although he is ultimately happy with the results and is already thinking about starting again. By his own measurements, he says he grew several inches between the ages of about 15 and 17 by taking the erda on and off. He says his height had previously plateaued.
A few more centimeters
Adalbert Raimann, a pediatric endocrinologist at the Medical University of Vienna in Austria, is the author of a study on erdafitinib often cited by Heightmaxxers. Published online in July 2024 in the peer-reviewed journal Hormonal research in pediatricshe describes unexpected growth in two children with central nervous system tumors.
Raimann explains that during puberty, growth takes place in the cartilage near the ends of bones, called growth plates. These plates fuse together once we reach our full size, around early adulthood. Erdafitinib blocks proteins called fibroblast growth factor receptors. One of them, FGFR3, normally helps limit bone growth; blocking it can allow growth to accelerate while the plaques are still active.
In a video chat, Raimann emphasizes that the reason these children were given this medication is important. Doctors were trying to keep children with rare and life-threatening cancers alive after other treatments had failed. This meant using a drug not approved for children and tolerating serious side effects.
“And these receptors that we target with erda are present in virtually every cell,” he says. “So we have no idea, neither among adults, nor especially among children in this developing system, of what we will be doing in five to ten years.”
Once these growth plates are completely closed, Raimann says, there is no way to grow naturally. This is why some adults in the heightmaxxing world are turning to dangerous and excruciating leg lengthening surgeries, which involve cutting the leg bones and gradually separating the sections so that new bones grow in the gaps. This is also why the population eager for experimental treatments is so young. The teens I spoke with felt like this was potentially their last chance to intervene.
For James, a 17-year-old from the West Coast who asks that I use only his first name, an X-ray helped kickstart his search for something that could make him taller. During our Zoom call, he holds up a translucent plastic container where he keeps the powder he identifies as erda. Then he brings his hand towards the webcam, curling his fingers to show me his nails. They are yellowish and ooze pus. He says they fell. “Brother, it’s bad.”
“I just thought I was going to be a late bloomer because my uncles and my dad grew up really late,” he says. “So I had a bone x-ray and the doctor said I was 18. Maybe I could grow an extra millimeter. And I was 5’9, so that was pretty bad. So I knew there had to be something that could make me taller.”
He says he started taking Erda in late August and grew about two to three inches in two months, while also consuming other medications. “I grew more in two months than in a year,” he says.
Erda wasn’t the first drug James had thought of. Doctors already prescribe growth hormone to help some children gain height, providing a hormone produced naturally by the body. Andrew Dauber, a pediatric endocrinologist at Children’s National Hospital in Washington, D.C., says there’s a distinction between treating a hormone deficiency and intervening because a child is simply small.
“There are children who are growth hormone deficient, who have severe growth problems, who really need growth hormone medically, as indicated. And then there is this gray area of using growth hormone for short stature,” he says. The FDA also approves it for some children whose short stature has no identified cause, a category called idiopathic short stature. Dauber describes the threshold as “a height less than minus 2.25 standard deviations.” This translates to an adult male being five foot three and an adult female being four foot 11.
Although guidelines are set by the FDA, doctors have the option to prescribe growth hormone off-label to people who they believe might benefit from it. The decision involves expensive and risky treatment, Dauber says, and doctors disagree on when it is justified.
“I’ve talked to a lot of pediatric endocrinologists, and some say, ‘Look, I know they’re going to get it. They’re either going to get it off the Internet or they’re going to go to a doctor who doesn’t know a lot about it, and I feel like I should just give it to them and at least monitor them for safety reasons and do it in a safer way,'” he says. “And then, many endocrinologists think it’s not really a disease or a medical problem.”
Dauber says he has now received his first patient inquiry regarding erda. He will not prescribe it for growth. “It’s way too dangerous. We only know about it in chemotherapeutic doses,” he says, referring to the amounts used to treat cancer.
At any rate
James says that when he was younger, his parents refused to let him take growth hormone. After an endocrinologist told him he was almost done growing at five feet five inches, he says, their guilt over that decision made them more permissive about his experiments with Erda and other drugs. “They kind of let me do everything,” he says.
Zak says his parents “don’t approve of anything I do.”
Both say nothing would stop them from trying everything they can to grow. “There’s this life I have in mind, and I want it so much that I’m not going to let any risk stop me from having the life I want,” James says. “I don’t know. I want it so bad.”
There has been a marked shift toward DIY healthcare in recent years, as alternative medicine and biohacking protocols gain popularity. People on social media are increasingly promoting injectable peptides and other invasive methods…
Gn Health
